1. Field
Methods and apparatuses consistent with the disclosed embodiments relate to processing an audio signal, and more particularly, to encoding/decoding a multi-channel audio signal by using semantic information.
2. Description of the Related Art
Examples of a general multi-channel audio encoding algorithm include parametric stereo and Moving Pictures Experts Group (MPEG) surround. In parametric stereo, two channel audio signals are down-mixed in a whole frequency region and a mono-channel audio signal is generated. In MPEG surround, a 5.1 channel audio signal is down-mixed in a whole frequency region and a stereo channel audio signal is generated.
An encoding apparatus down-mixes a multi-channel audio signal, adds a spatial parameter to the down-mixed channel audio signal, and performs coding on the audio signal.
A decoding apparatus up-mixes the down-mixed audio signal by using the spatial parameter and restores the original multi-channel audio signal.
In this regard, when the encoding apparatus down-mixes predetermined channels, the decoding apparatus does not easily separate the channels, which deteriorates spatiality. Therefore, the encoding apparatus needs an efficient solution for easily separating channels which are down-mixed.